Observational limits on the X-ray emission from the bubble nebula surrounding Ho IX X-1

Abstract

Optical and radio observations of shock-ionised bubble nebulae surrounding ultraluminous X-ray sources (ULXs) suggest that they are powered by jets or super-critical outflows presumably launched from the ULX accretion disc. Recent simulations of these systems have shown that the shocked wind can emit thermal X-rays with estimated luminosities $\sim 10^{36}$ erg s${}^{-1}$. In this work, we investigated whether it is possible to detect and spatially resolve the X-ray emission from these systems using archival Chandra observations of the ULX Holmberg IX X-1. This source is an ideal target to study for two reasons: it is surrounded by an optical bubble nebula with a large spatial extent ($\sim$ 400 pc) that can easily be resolved with Chandra. Further, it has a hard X-ray continuum that is easily distinguishable from the expected soft thermal emission from the nebula. However, a spectral and photometric analysis on stacked Chandra observations of the source reveals that there is no strong evidence for an X-ray bubble associated with it, to a limiting luminosity of $\sim 2\times 10^{36}$ erg s${}^{-1}$. The detection of such X-ray nebulae may be possible with future X-ray missions such as Athena, which would provide useful constraints on the kinematics of the outflow. Finally, our observations also emphasise that the nebular emission does not contribute significantly to the residuals in the X-ray spectrum of the source, which are more likely to be linked to processes localised to the ULX.

arXiv comment9 pages, 6 figures; accepted for publication in MNRAS

References in corpus (34)

• On the Absorption of X-rays in the Interstellar Medium
• The Leiden/Argentine/Bonn (LAB) Survey of Galactic HI: Final data release of the combined LDS and IAR surveys with improved stray-radiation corrections
• Collisional Plasma Models with APEC/APED: Emission Line Diagnostics of Hydrogen-like and Helium-like Ions
• An Ultraluminous X-ray Source Powered by An Accreting Neutron Star
• Super-critically accreting stellar-mass black holes as ultraluminous X-ray sources
• Ultraluminous X-Ray Sources
• The Ultraluminous State
• Discovery of a 0.42-s pulsar in the ultraluminous X-ray source NGC 7793 P13
• Discovery of coherent pulsations from the Ultraluminous X-ray Source NGC 7793 P13
• The ultraluminous state revisited: fractional variability and spectral shape as diagnostics of super-Eddington accretion
• Resolved atomic lines reveal outflows in two ultraluminous X-ray sources
• A mass of less than 15 solar masses for the black hole in an ultraluminous X-ray source
• X-ray emission from star-forming galaxies - II. Hot interstellar medium
• A spectral-timing model for ULXs in the super-critical regime
• High Resolution Imaging of the HeII lambda 4686 Emission Line Nebula Associated with the Ultraluminous X-Ray Source in Holmberg II
• ASMOOTH: A simple and efficient algorithm for adaptive kernel smoothing of two-dimensional imaging data
• Super-Eddington accretion disc around a Kerr black hole
• From ultraluminous X-ray sources to ultraluminous supersoft sources: NGC 55 ULX, the missing link
• Diagnosing the accretion flow in ultraluminous X-ray sources using soft X-ray atomic features
• Broad absorption features in wind-dominated ULXs?
• Optical counterparts of the nearest ultraluminous X-ray sources
• Evidence for an Intermediate Mass Black Hole in NGC 5408 X-1
• The unusual supernova remnant surrounding the ultraluminous X-ray source IC 342 X-1
• A Study of Cepheids in M81 with the Large Binocular Telescope (Efficiently Calibrated with HST)
• An Optical Study of Stellar and Interstellar Environments of Seven Luminous and Ultraluminous X-Ray Sources
• Searching for Outflows in Ultraluminous X-ray Sources Through High-Resolution X-ray Spectroscopy
• X-ray spectral evolution in M33 X-8
• X-ray Outflows and Super-Eddington Accretion in the Ultraluminous X-ray Source Holmberg IX X-1
• The X-ray spectral evolution of the ultraluminous X-ray source Holmberg IX X-1
• Accretion Rates and Beaming in Ultraluminous X-ray Sources
• The Broadband Spectral Variability of Holmberg IX X-1
• The First Detection of [O IV] from an Ultraluminous X-ray Source with Spitzer I. Observational Results for Holmberg II ULX
• Evolution of the spectral curvature in the ULX Holmberg II X-1
• Optical and X-ray luminosity of expanding nebulae around ultraluminous X-ray sources

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